RFR: 8220411: Remove ScavengeRootsInCode=0 code

[Tobias Hartmann]

Hi Stefan,

this looks good to me.

Best regards,
Tobias

On 11.03.19 11:26, Stefan Karlsson wrote:
> Updated webrev after some offline feedback from ErikÖ:
> 
>  http://cr.openjdk.java.net/~stefank/8220411/webrev.02.delta
>  http://cr.openjdk.java.net/~stefank/8220411/webrev.02
> 
> - I've removed can_be_constant and updated the code where it was used.
> - Removed and replaced check_oop with oopDesc::is_oop_or_null checks.
> 
> Thanks,
> StefanK
> 
> On 2019-03-11 09:57, Stefan Karlsson wrote:
>> Hi all,
>>
>> Please review this patch to remove code that checks and acts upon ScavengeRootsInCode=0.
>>
>> http://cr.openjdk.java.net/~stefank/8220411/webrev.01/
>> https://bugs.openjdk.java.net/browse/JDK-8220411
>>
>> Since a while now, we have not supported -XX:ScavengeRootsInCode=0, and the code actively sets it
>> to 1 if the user passes in 0. This patch removes the actual code, there's another RFE to deal with
>> changing the argument handling to explicitly not support that the flag is set to 0. See: JDK-8144954.
>>
>> My main motivation for this patch is to get rid of some of the usages of
>> CollectedHeap::is_scavengable. The intention is that later patches will completely remove that
>> function.
>>
>> Thanks,
>> StefanK